Improvement in screw-cutting dies



UNITED STATES PATENT OFFICE.

JIREH. CASE SHERMAN, OF NEW BEDFORD, MASSACHUSETTS.

IMPROVEMENT IN SCREW-CUTTING DIES.

Specification forming part of Letters Patent No. 168,349, dated October 5, 1875; application filed August 4, 1875.

To all whom it may concern:

Be it known that I, JIREH O. SHERMAN, of New Bedford, Bristol county, and State of Massachusetts, have invented an Improved Changeable Die, of which the following is a specification, reference being had to the accom panying drawings forming part hereof.

My invention consists in a die-stock in which are adjusted in suitable openings cutters of the form hereinafter described, held in position by means of clamp-rings fitted in channels formed in the faces of the stock,whereby the cutters are firmly held adjusted in the stock, or may be conveniently changed, and cutters of different lengths inserted; or may be inexpensively duplicated or tempered, or be altered in the stock from right to left hand threads.

Figure 1 is a plan of a die embodying my invention. Fig. 2 is a cross-section of the same on the line m as, Fig. 1. Fig. 3 is a detached View of the cutter.

A is the stock,which is preferably made of iron, case-hardened, and is formed with the central opening f and the radial openings a, as shown, and with the circular channels I), one in each face of the stock, as shown. B B are rings, preferably of the same material as the stock,

arranged to fit snugly in the channels I), as shown, where they are held by the bolts or screws 8. The cutters G are formed as shown in Fig. 3, adapted to fit closely in the openings at in the stock, and with the cutting-face c projecting into the opening f, and the shank d, which has the channels e formed one on each side, as shown, and corresponding to and of the same depth as the channels b in the stock.

Now, it is evident that the cutters C may be readily adjusted in the openings at, as shown in Fig. l, and held firmly therein in proper position by the clamp-rings B, secured by the bolts or screws, and that they may be conveniently and readily changed, and cutters of different lengths inserted; or may be inexpensively duplicated, or removed and tempered, or be altered in the die from right to left hand threads, or the reverse.

What I claim as my invention, and desire to secure by Letters Patent, is

The combination of the die-stock A, provided with the openings (1., channels I), and rings B, and the cutters O, as described.

JIREH CASE SHERMAN.

Witnesses:

H. J. FULLER, J. H. GALLIGAN. 

